Patients continue antiretroviral medications throughout the course of this study. Three groups of patients receive dose-escalation (2×10^9VP, 2×10^10VP or 2×10^11VP) injections of Adenovirus vector vaccine (Ad5-gag). Two weeks post immunization of lower dose, if the vaccine is safe and well tolerant, the next dose of immunization will begin. patients are monitored for safety 72 hours after each immunization. In addition, each patient records adverse events in a diary. Patients have regular physical exams, pregnancy tests, and blood drawn for virologic and immunologic assessments. The induction of HIV-specific responses will be measured.